San Marino Grand Prix, Sunday 23 April, 1300 BST
World champion Fernando Alonso set the fastest time in the second free practice session for this weekend's San Marino Grand Prix at Imola.
Alonso leads the drivers' standings after three races
Renault's Alonso clocked one minute 25.043 seconds to beat Ferrari's Michael Schumacher by 0.328 seconds.
Schumacher was the quickest for the day, having lapped in one minute 24.751 seconds in the morning session.
Ferrari's Felipe Massa was the third fastest racer in the second session, from Renault's Giancarlo Fisichella.
Britain's Jenson Button was 10th quickest for Honda, while David Coulthard was 19th in his Red Bull.
Despite setting the fastest time, Alonso said there was work still to be done.
"We are not there yet, and we are suffering from too much understeer at the moment," said the Spaniard.
"If we can make some good changes tonight, though, I think we will be a in a strong situation for the race."
Schumacher said he was "happy" with his car's performance and believes that he can challenge for victory at Ferrari's home track.
"The car is going very well. The whole package has improved - in all areas we have found solutions and improvements," said the German.
"To my eyes, yes, we can fight for victory."
Button was also upbeat despite finishing down in 10th.
"It's not looking too bad," he said. "It's very similar to Malaysia when we made a lot of set-up changes and suddenly the car came good.
"We know what the issues are and we know we can solve them. Hopefully we can be on the pace and I think we will be."
Most of the drivers had to contend with dirty tyres on their first flying laps in the afternoon because the pit lane was covered in concrete dust after a driver from a support race spilled some oil.
This caused Alonso, McLaren's Kimi Raikkonen and BMW Sauber's Nick Heidfeld to skid off the track.
But Spain's Alonso survived his scare at the Variante Alta chicane to set the pace with just three minutes of the session remaining.
Raikkonen could manage only 11th, while Button's team-mate Rubens Barrichello was 12th fastest.
Honda's reserve driver, Anthony Davidson of Britain, was fourth fastest in the second session and fifth in the first.
Williams pair Nico Rosberg and Mark Webber, along with Button, did not leave the garage in the morning session, and were 15th and 17th fastest respectively in the second session.
Combined times from Friday's two practice sessions at the San Marino Grand Prix:
1. Michael Schumacher (Ger) Ferrari, 13, 1:24.751*
2. Fernando Alonso (Spa) Renault, 15, 1:25.043
3. x-Alexander Wurz (Aut) Williams, 31, 1:25.132*
4. x-Robert Kubica (Pol) BMW-Sauber, 31, 1:25.421
5. x-Anthony Davidson (GB) Honda, 31, 1:25.699
6. Felipe Massa (Brz) Ferrari, 16, 1:25.879
7. Giancarlo Fisichella (Ita) Renault, 15, 1:25.991
8. Jarno Trulli (Ita) Toyota, 24, 1:26.029
9. Juan Pablo Montoya (Col) McLaren-Mercedes, 15, 1:26.334
10. Jenson Button (GB) Honda, 7, 1:26.427
11. x-Robert Doornbos (Mon) Red Bull-Cosworth, 24, 1:26.498*
12. Kimi Raikkonen (Fin) McLaren-Mercedes, 12, 1:26.500
13. Rubens Barrichello (Brz) Honda, 16, 1:26.653
14. David Coulthard (GB) Red Bull-Cosworth, 6, 1:26.678*
15. Christijan Albers (Ned) Midland, 19, 1:26.783
16. Nico Rosberg (Ger) Williams, 13, 1:26.989
17. Vitantonio Liuzzi (Ita) Scuderia Toro Rossa, 27, 1:27.128
18. Mark Webber (Aus) Williams, 10, 1:27.157
19. Jacques Villeneuve (Can) BMW-Sauber, 24, 1:27.517
20. Tiego Monteiro (Por) Midland, 12, 1:27.544
21. Nick Heidfeld (Ger) BMW-Sauber, 20, 1:27.561
22. Ralf Schumacher, Germany, Toyota, 5, 1:27.639
23. Scott Speed (US) Scuderia Toro Rossa, 25, 1:27.719
24. Christian Klien (Aut) Red Bull-Cosworth, 12, 1:27.990
25. x-Neel Jani (Swi) Scuderia Toro Rosso, 21, 1:28.361
26. x-Giorgio Mondini (Swi) Midland, 27, 1:28.833
27. Takuma Sato (Jpn) Super Aguri, 23, 1:29.870
28. Yuji Ide (Jpn) Super Aguri, 20, 1:31.042
x = test driver not eligible to race; * = time set in first session